24 ALASKAN GLACIER STUDIES dition are described in several publications.1 In the reports of the work up to and including 1905 the glaciers of the Yakutat Bay region are fully described, and their more significant features interpreted. With a single exception, that of Galiano Glacier, the glaciers were found to be wasting, and recession was the rule between 1890 and 1905, as Russell's observations clearly show had been the general condition for years before his first visit of 1890. Apparently having no bearing on the problems of the glaciers and glaciation, but in reality of the greatest significance, were the observations of 1905 upon the effects of the great earthquakes which disturbed the Yakutat Bay region in September, 1899.2 For on returning to Yakutat Bay in 1906, the senior author, in charge of a second United States Geological Survey expedition, found that several of the hitherto-wasting glaciers had begun a sudden activity in response to an impulse derived from the down-shaking of great masses of snow in the glacier reservoirs during the earthquakes of 1899.8 The National Geographic Society's Alaskan Expeditions of 1909-10 went first to Yakutat Bay in order to determine what further changes had taken place in the interval since 1906. Since these later observations 4 fill out and verify those of the two previous expeditions, making, as it were, a complete story, it seems fitting to take up the Yakutat Bay region as a whole, describing and interpreting its glaciers and glacial phenomena in the light of all the studies from those of Russell in 1890 down to and including those of the season of 1913, when the junior author visited Yakutat Bay in charge of an excursion of the International Geological Congress. Location and General Physiographic Features.6 Yakutat Bay is an indentation in the otherwise almost unbroken coast line that stretches between Cross Sound and Controller Bay, its mouth being near latitude 59° 40' north and longitude 140° west. It is about 40 miles southeast of Mt. St. Elias, and very near the point where the boundary line 1 Tarr, R. S. and Martin, Lawrence, Observations on Glaciers and Glaciation of Yakutat Bay, Alaska: Bull. Amer. Geog. Soc., Vol. XXXVULL, 1906, pp. 99-101; Glaciers and Glaciation of Yakutat Bay, Alaska, Bull. Amer. Geog. Soc., Vol. XXXVm, 1906, pp. 146-167; Position of Hubbard Glacier Front in 1792 and 1794; Bull. Amer. Geog. Soc., VoL XXXIX, 1907, pp. 129-186. Tarr, R. S., Glacial Erosion in Alaska: Pop. ScL'Monthly, VoL T.TT, 1907, pp. 99-119. * Tarr, R. S. and Martin, Lawrence: Recent Change of Level in Alaska: Science, Vol. XXTT, 1906, pp. 879-880; Recent Changes of Level in the Yakutat Bay Region, Alaska: Bull. Geol. Soc. Amer., Vol., XVII, 1906, pp. 29-64; Recent Change of Level in Alaska; Geog. Journ., Vol. 2L2LVULL, 1906, pp. 80-13; The Yakutat Bay Earthquakes of September, 1899, Professional Paper 69, U. S. Geol. Survey, 1912, pp. 11-30. Martin, Lawrence, The Alaskan Earthquakes of 1899, Bull. Geol. Soc. Amer., Vol. XXI, 1910, pp. 339-407. »Tarr, R. S., The advancing Malaspina Glacier: Science, Vol. XXV, 1907, pp. 84-37; Second Expedition to Yakutat Bay, Alaska; Bull. Geog. Soc. Phila., Vol. V, 1907, pp. 1-14; The Malaspina Glacier: Bull. Amer. Geog. Soc., Vol. XXXIX, 1907, pp. 278-286; Recent Advance of Glaciera in the Yakutat Bay Region, Alaska: Bull. Geol. Soc. Amer., Vol. 18, 1907, pp. 267-286. Also incorporated in the final report for the two expeditions of 1906 and 1906 in the section on Physiography and Glacial Geology of the Yakutat Bay Region, Alaska, Professional Paper 64, U. S. GeoL Survey, 1909, pp. 1-144. «Tarr, R. S. and Martin, Lawrence, The National Geographic Society's Alaskan Expedition of 1909, Nat. Geog. Mag., Vol. XXT, 1910, pp. 1-64. Martin, Lawrence, The National Geographic Society Researches in Alaska, Nat. Geog. Mag., Vol. XXII, 1911, pp. 637-661; The Hubbard Glacier, Pop. Sci. Monthly, Vol. 76, 1910, pp. 298-306; Gletscherunter-suchungen langs der Kilste von Alaska, Petermanns Geog. Mitteilungen, Jahrgang 1912, pp. 78-79; Guide Book No. 10, Excursion C 8, International Geological Congress, Ottawa, 1913, pp. 134-162. *For a more complete discussion of the physiography of the Yakutat Bay region see Tarr, R. S., Physiography and Glacial Geology, Professional Paper 64, U. S. Geol. Survey, 1909. For area! geology, see Tarr, R. S. and Butler, B. S., ibid, pp. 146-164.